In the field of liquid crystal display, a display substrate is an important part of a display panel for achieving color display. In the conventional manufacturing process of a display substrate, a black matrix is usually formed on a transparent substrate such as glass, and a color film layer is formed on the substrate that already has the black matrix formed thereon. Exposure→Development process is an important process during manufacturing of the color film layer, and it is usually performed using an exposure device, where the exposure device automatically detects a pre-set exposure alignment mark in real time and aligns a mask plate having a pattern of the color film layer with the alignment mark. Specifically, the conventional alignment process may comprise aligning the transparent substrate with a stage of the exposure device and forming a black matrix and black matrix alignment marks; aligning the substrate on which the black matrix is formed with the stage of the exposure device; and aligning the black matrix with a mask for the color film layer, wherein the alignment of the black matrix with the mask for the color film layer is achieved by aligning the black matrix alignment marks with the color film layer alignment marks.
However, when there is just a spacing offset of an integral number of alignment marks between the black matrix alignment marks and associated color film layer alignment marks, the alignment may be considered by the exposure device as having no alignment error, which thus results in misjudgment.